In the late 70s (and beyond) Space Invaders ruled the arcade roost. Other companies didn't want to risk competing with this video game phenomenon, so they produced a lot of similar games, hoping to get a small share of the quarter-wielding teenage horde. Namco took the concept of Space Invaders and added their own twist, breaking through its monopoly.

Galaxian introduced many innovation to the fixed-shooter, shoot-the-aliens genre. Action played out in true color, with multi-colored explosions and a scrolling starfield as background. There were also graphic representations of how many ships a player had left and how many rounds had been completed. The player's ship moved from left to right a the bottom of the screen and waited as the insect-like aliens enter the playfield and arranged themselves in various flying formations.

The real draw of the game was the in the enhanced abilities of the alien swarm. While they relied mostly on exchanging fire with your own ship, they periodically swooped down at you, kamikaze-style. Destroying the swarm meant another one took its place, firing and swooping more aggressively than before.

The RGB colors, the drama of divebombing insects and the enhanced graphics led to a mightily impressed arcade crowd that flocked to the innovative game. Galaxian gave rise to many follow-up games, most notably Galaga, which eclipsed its predecessor with the addition of bonus rounds and aliens with tractor beams.